From c44b43f33e0e4fedb38ea490cff9f357079e9c12 Mon Sep 17 00:00:00 2001
From: Jesse Luehrs <doy@tozt.net>
Date: Thu, 8 Dec 2022 01:09:33 -0500
Subject: simplify

---
 src/2022/8/mod.rs | 50 ++++++++++++++++++++++++++++++++------------------
 src/grid.rs       | 14 ++++++++++++++
 2 files changed, 46 insertions(+), 18 deletions(-)

diff --git a/src/2022/8/mod.rs b/src/2022/8/mod.rs
index 59f561c..49df9dd 100644
--- a/src/2022/8/mod.rs
+++ b/src/2022/8/mod.rs
@@ -9,27 +9,37 @@ pub fn parse(fh: File) -> Result<Grid<u8>> {
 
 pub fn part1(trees: Grid<u8>) -> Result<i64> {
     let mut total = 0;
-    for row in (0..trees.rows().0).map(Row) {
-        'tree: for col in (0..trees.cols().0).map(Col) {
+    for row in trees.each_row() {
+        'tree: for col in trees.each_col() {
             let tree = trees[row][col];
 
-            if (0..col.0).map(Col).all(|col| trees[row][col] < tree) {
+            if trees
+                .each_col()
+                .take(col.0)
+                .all(|col| trees[row][col] < tree)
+            {
                 total += 1;
                 continue 'tree;
             }
-            if ((col.0 + 1)..trees.cols().0)
-                .map(Col)
+            if trees
+                .each_col()
+                .skip(col.0 + 1)
                 .all(|col| trees[row][col] < tree)
             {
                 total += 1;
                 continue 'tree;
             }
-            if (0..row.0).map(Row).all(|row| trees[row][col] < tree) {
+            if trees
+                .each_row()
+                .take(row.0)
+                .all(|row| trees[row][col] < tree)
+            {
                 total += 1;
                 continue 'tree;
             }
-            if ((row.0 + 1)..trees.rows().0)
-                .map(Row)
+            if trees
+                .each_row()
+                .skip(row.0 + 1)
                 .all(|row| trees[row][col] < tree)
             {
                 total += 1;
@@ -42,13 +52,14 @@ pub fn part1(trees: Grid<u8>) -> Result<i64> {
 
 pub fn part2(trees: Grid<u8>) -> Result<i64> {
     let mut max = 0;
-    for row in (0..trees.rows().0).map(Row) {
-        for col in (0..trees.cols().0).map(Col) {
+    for row in trees.each_row() {
+        for col in trees.each_col() {
             let tree = trees[row][col];
 
             let mut seen = false;
-            let left = (0..col.0)
-                .map(Col)
+            let left = trees
+                .each_col()
+                .take(col.0)
                 .rev()
                 .take_while(|col| {
                     if seen {
@@ -66,8 +77,9 @@ pub fn part2(trees: Grid<u8>) -> Result<i64> {
                 .count();
 
             let mut seen = false;
-            let right = ((col.0 + 1)..trees.cols().0)
-                .map(Col)
+            let right = trees
+                .each_col()
+                .skip(col.0 + 1)
                 .take_while(|col| {
                     if seen {
                         return false;
@@ -84,8 +96,9 @@ pub fn part2(trees: Grid<u8>) -> Result<i64> {
                 .count();
 
             let mut seen = false;
-            let up = (0..row.0)
-                .map(Row)
+            let up = trees
+                .each_row()
+                .take(row.0)
                 .rev()
                 .take_while(|row| {
                     if seen {
@@ -103,8 +116,9 @@ pub fn part2(trees: Grid<u8>) -> Result<i64> {
                 .count();
 
             let mut seen = false;
-            let down = ((row.0 + 1)..trees.rows().0)
-                .map(Row)
+            let down = trees
+                .each_row()
+                .skip(row.0 + 1)
                 .take_while(|row| {
                     if seen {
                         return false;
diff --git a/src/grid.rs b/src/grid.rs
index b84e1b7..f360932 100644
--- a/src/grid.rs
+++ b/src/grid.rs
@@ -110,10 +110,24 @@ impl<T: Default + Clone + Eq + PartialEq> Grid<T> {
         Row(self.rows.len())
     }
 
+    pub fn each_row(
+        &self,
+    ) -> impl Iterator<Item = Row> + DoubleEndedIterator + ExactSizeIterator
+    {
+        (0..self.rows().0).map(Row)
+    }
+
     pub fn cols(&self) -> Col {
         Col(self.rows[0].cells.len())
     }
 
+    pub fn each_col(
+        &self,
+    ) -> impl Iterator<Item = Col> + DoubleEndedIterator + ExactSizeIterator
+    {
+        (0..self.cols().0).map(Col)
+    }
+
     pub fn get(&self, row: Row) -> Option<&GridRow<T>> {
         self.rows.get(row.0)
     }
-- 
cgit v1.2.3-54-g00ecf